Electric-vehicle control



Nov. 20, 1 23. 4 1,474,942

K. PROBST ELECTRIC VEHICLE CONTROL Filed Feb. 13. 1922, 2 Sheets-Sheet 1 Chi Nev. 20 1923. 1,474,942-

K. PROBST ELECTRIC VEHIYQE'AE CONTROL Filed Eels. 13, 1.922 2 Sheets-Sheet 2 .351, Wm WM HfZM W Patented Nov. 20, 1923.

UNITED STATES KARL PROIBST, or TOLEDO, OHIO.

ELECTRIC- VEHICLE CONTROL.

Application filed February 13, 1922. Serial No. 535,988..

To all whom it may concern: Be it known that I, IsrAnr. Pnoes'r, a citi- "zen of the United States of America, residing at Toledo, in the county of Lucas and State of Ohio, have invented certain new and useful Improvements in Electric-Vehicle Controls, of which the following-is a specification, reterencebeing had therein to the accompanying drawings.

The invention relates to electric vehicles of the type operated by storage batteries, and it is the object of the invention to obtain greater efficiency or economy in current consumption; a longer life of the batteries;

also, longer life of the vehicle parts due to smoother starting. In the present state of the art the common type of control used for regulating the speed and torque of the motor is a system where a single controller in successive positions of adjustment both varies the motor connections and the battery connections alternatively in series or parallel, and the arrangement is such as to furnish a plurality of speeds by successive adjustments with the last adjustment furnishing the highest voltage and'greatest current consumption. If such a control is carefully manipulated, it is possible to obtain both efiiciency and any desired speed without injurious effect, but unfortunately the average driver will not exercise the care required for such result. Thus in starting the car, instead of slowly manipulating the controller to pass from one position to another, the operator will frequently quickly adjust to the highest position, thereby drawing a volume of current which is wasteful of the energy and is detrimental to the electrical parts. It the controller is so designed as to avoid this result, then there will not be sutficient current for the maximum demand. For instance, with an electrically driven delivery wagon, it may be necessary to provide for a maximum speed of 15 to 35 miles an hour for long distance traveling, whereas the average speed required for house to house delivery may be very much less. This average speed could be obtained from a parallel connection of the batteries giving a low voltage, but for the higher speed a series connection giving a: high voltage is necessary. It, therefore, the controller is so designed as to give in its highest position of adjustment the high voltage required for the maximum speed, there is nothing to prevent the careless operator from adjusting to this position in its house to house delivery, although no material advantage in speed is obtained.

It is the primary object of the present invention to so design the control that the operator can not, without deliberately vio lat-ing instructions, waste current in the normal operation of the machine or strain the electrical parts. At the same time provision is made for obtaining the higher voltage and, secondly, greaterspeed where necessary. The desired results are obtained by dividing the control into separately oper able units, one for normal operation and the other for abnormal operation. More specifically, there is provided one control unit for varying the speed of the motor by changing motor or rheostat connections or both while the other unit provides for change in voltage by shifting from parallel to series connection of the batteries. Thus in normal operation, where the vehicle is driven from house to house, there is no occasion for using the battery control, this being adjusted to give a parallel arrangement of the batteries and low voltage. However, it is possible at any time where the vehicle is traveling long distances, to increase the speed by changing the battery control to the series arrangement.

In the drawings Figure 1 represents diagrammatically my improved system ofcontrol;

Figure 2 is a side elevation oiithe battery controlling switch;

Figure 3 is an end elevation. thereof.

A. and B represent two equal sections of the storage battery. C is the motor, and

D the controller for normal operation E is an auxiliary controller which is used only for maximum speed. The controller D may be of any suitable construction (not shown in detail) and may be connected to the motor so as to control the latter either by variation in the connection to the internal winding or by use of an external rheostat, or both, these forming no part of my invention. The auxiliary controller E may also be of any suitable construction, but as specifically shown in Figures 2 and 3, it consists in a pair of switch blades F and F which are pivoted to the contacts G and G and may be alternatively connected to the contacts H, H or I, I. The circuits, as

diagrammatically shown include a connec- 5 l), a connection M from the controller D to the contact G, a connection N from the negative pole of the battery A to the contact II, and a connection 0 from the positive pole of the battery B to the contact G. There is also a cross-connection P between the contacts II and I, a connection Q, from the negative pole of the battery A to a char er coupling, and a connection R -from the positive pole of the charger coupling to the contact I. As the design of the main controller I) or the particular connections rsed between the same and the motor are not esscstial to the invention, these are not illustrated in detail.

Vith the arrangement oi circuits as described, when the switch E is adjusted with the blades I! and F, connecting respectively the contacts G. H, and H as shown in full lines in Figure l, the batteries A and B are connected in parallel and in this position current at low voltage is supplied to the controller D and from the latlet to the motor. lVhen the switch E is adjusted with the blades F and F, connecting respectively the contacts G, I, and l, I, as indicated in dotted lines in Figure 1, the batteries A and B are connected in series and "furnish current at high voltage to the controller. Also, in this latter position the charger coupling is connected so that the battery may be charged by engaging said coupling with a suitable source of charging current.

lVhen the switch E is adjusted for low voltage, the vehicle may be used for house to house delivery and there is seldom, if ever, any occasion for using the higher voltage iior this purpose. Thus the greatest etliciency or economy of current is obla ied; the life of the electric parts due to low current handling is increased; and the mechanical parts oi the vehicle have longer lite due to smoother starting ot the vehicle. (in the other hand, when speed is important, the switch E may be shii'tcd lo high voltage.

What I claim as my invention is:-

1. In an electrically driven vehicle, the combination with a motor and a storage battery comprising two equal sections, of a controller for varying the speed of the motor without change in battery Voltage,

a charger connection for the battery, and a switch for alternatively coupling said battery sections in parallel and in series and for effecting in the latter position a coupling with said charger.

2. In an electrically driven vehicle, the combination with a motor and a storage battery, of a controller for varying the speed of the motor without changing battery voltage, a charger connection for the battery, and separately operable means for controlling the voltage, said meansalso ettecting a coupling with said charger in one position of adjustment.

In an electrically driven vehicle, the combination with a motor and a storage battery, of a controller for varying the speed. of the motor without changing battery voltage, a switch for changing the bat tery connections from parallel to series, and a charger connected to said switch to effect a coupling with said battery in only one position of adjustment.

4. In an electrically driven vehicle, the combination with a motor and a storage battery, of a controller for varying the speed of the motor without changing battery voltage, a switch for changing the battery connections from parallel to series, and acharger connected to said switch to effect a coupling with said battery only when the latter is in series arrangement.

In an electrically driven vehicle, the combination with a motor and a storage battery comprising a plurality of sections, of a controller for varying the speed of the motor without changing battery voltage, separately operable means for coupling said battery sections together in different arrangements to vary the effective voltage, and a charger arranged to be coupled with said battery in only one of said different arrangements of battery sections.

(5. In an electrically driven vehicle, the combination wit-h a motor and a storage battery comprising two equal sections, of a controller for starting said motor and varying the speed thereof, a separately oper able switch tor connecting said battery sec tions alternately in parallel and series, and a charger arranged to be coupled with said battery only when said. sections are in se ries arrangement In testimony whereof I afiix my signature.

KARL PROBST. 

